Mark cpu profiler test as flaky on windows.

TBR=yurys@chromium.org
BUG=v8:2999
LOG=no

Review URL: https://codereview.chromium.org/120543002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18400 ce2b1a6d-e550-0410-aec6-3dcde31c8c00